"Let's Increase the Use of Tetracyclines to Decrease C. difficile colitis" by Steven P. LaRosa, M.D.
Physicians are quite comfortable with the use of the tetracycline antibiotics Doxycycline and Minocycline in tickborne infections and acne. Short of these two indications this class of antibiotics is rarely reached for. A new study by Raseen Tariq and colleagues in Clinical Infectious Disease 2018;66(4):514-522 should change that. A meta-analysis of 6 studies demonstrated that tetracyclines were associated with a decreased risk of C diff Infection (CDI) (odds ratio 0.62, 95% CI , 0.40-0.81; p < .001. This decreased risk held when just Doxycycline was examined. There are at least 2 potential biologic explanations for this observed effect. The first is that tetracycyclines cause fewer and shorter lasting perturbations to the fecal microbiota than other classes of antibiotics. The second is that enteral delivery of tetracyclines has inhibitory effect on Clostridium difficile. In fact, Tigecycline, a glyclcycline relative of tetracyclines, has been used successfully as a salvage thera